Shallow Marine Surveys Group (SMSG)

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Shallow Marine Surveys Group (SMSG)

SMSG were formed in 2006 by marine biologists and dive enthusiasts in the Falkland Islands. The group recognised that the shallow marine environment in the Falkland Islands is pristine, un-impacted by man and surprisingly diverse but almost nothing was known about it. Their initial aim was to provide species inventories for the habitats of this vast coastline and ultimately to produce a guide book so others could enjoy the amazing sites, habitats and species that are contained within it. Since they started in 2006 over 500 species of algae and animals have been documented between the intertidal zone and 20 metres in depth. These range from inconspicuous algae the thickness of a single cell to migrating whales exceeding 15 tonnes. Some species are readily distinguished at a glimpse while others require a sharp eye to determine their identity. But each contributes to the biodiversity of the shallow marine environment – the most diverse environment in the Falklands Islands.

SMSG’s expeditions have taken them to the far reaches of the Falkland Islands, the north coast of sub-Antarctic South Georgia and the tropical oceanic island of Ascension. Their work has resulted in the discovery of over 30 new species, numerous habitats and unique faunal and floral communities. The environments the group work in range from a comfortable 26 °C to freezing cold conditions of less than 0 °C in South Georgia and strong winds can make seas and coastlines prohibitively rough. Exploration of the marine life in these environments therefore presents some challenges.

The theme of this set of stamps is rocky reef habitats in the three United Kingdom South Atlantic Overseas Territories. The species diversity and floral and faunal assemblages are extremely different in each of the territories and the reasons for this are due to latitude, oceanography and geographical isolation in terms of distance from other islands and continental land masses.

Ascension Island lies approximately 8° south of the equator, 145 km west of the centre of the mid-Atlantic Ridge. The nearest land is St Helena approximately 1,130 km to the southeast. The continental land masses of West Africa and Brazil are approximately 1,500 km and 2,400 km away respectively. Ascension is therefore one if the most isolated islands in the world. It is a young volcanic island of approximately 1 million old.

Few marine biological studies have taken place here prior to the 1970s. Since then the island has seen a few expeditions including two from the US National Museum of Natural History (Smithsonian Institution) making extensive collections particularly of crustaceans, molluscs and echinoderms. In the late 1970s the Natural History Museum, London investigated near-shore macroalgal communities. A few years later in 1985, a UK diving expedition led by Robert Irving catalogued and photographed sublittoral habitats. More recently studies of the island’s crustaceans and sponges were conducted by scientists form the Smithsonian and the National Museums of Wales.

Ascension Island’s waters are clear, its rocky reefs are covered with volcano like coralline algae and its sublittoral fauna is, at first glance, quite impoverished. This environment is dominated by fish, particularly the black trigger fish (Melichthys niger). This is a keystone species at Ascension Island due to its abundance, and its wide dietary niche. It grazes on just about anything leaving little in the way of algae and invertebrate fauna on the reefs. The reefs are a difference scene at night when the black fish are asleep. Sea urchins, sea cucumbers and a host of other invertebrates come out revealing a cryptic diversity not seen in the day.

The island’s isolation has resulted in its impoverished fauna and flora. Most of invertebrate species have their centres of distribution in the Caribbean and/or the coast of Brazil with very few associated with West African faunas. This is also true for most fishes: 30% of the 71 species of near-shore fishes are only recorded from the western and central Atlantic, whereas just 7% are recorded from the eastern and central Atlantic.

The issue consists of four stamps (45p, 50p, 60p & £1.45p) all with white borders, a sheetlet of 16 in staggered se-tenant format with the same values which bleed off and a souvenir sheet containing three £1 stamps, one of each from Ascension Island, Falkland Islands and South Georgia.

First Day Covers of the souvenir sheet will be cancelled first day of issue in Ascension Island and then forwarded for cds cancellations in Falkland Islands and South Georgia.